Capsules for holding medicines, dietary supplements, etc., are very well known and have been in commercial use for many years for human and veterinary use. They are typically made of a digestible gelatin-like material and contain a medicine in liquid or powder form or a dietary supplement, such as vitamins, fish oil, etc. in a single internal cavity (compartment). Moreover, such capsules are typically manufactured in certain standard sizes referred to as capsule size designated by numerals, such as 000, 00, etc. One of the most common sizes is the 00 capsule. This disclosure is generally of a capsule of 00 size, but this is not at all limiting but is merely illustrative. The typical 00 size capsule, in common with other capsules, has a standardized nominal volume. For instance, a 00 capsule has a volume of approximately 0.95 milliliters. The typical weight of such a typical capsule is 119 milligrams. Such capsules typically have two parts, a cap and a body, which are bonded together. The typical nominal length of the cap (along the long axis of the capsule) is 11.8 mm, plus or minus 0.4 mm. The length of the body (also as a separate component) is 20.2 mm plus or minus 0.4 mm. The overall assembled length of such a capsule is 23.5 mm plus or minus 0.4 mm. The outside diameter of the cap is typically 8.5 mm plus or minus 0.03 mm and the outside diameter of the body, which is slightly smaller than that of the cap, since typically the cap fits over the body when assembled, is 8.22 mm, plus or minus 0.03 mm. Other sizes of capsules each have their own nominal dimension
Most such capsules only contain a single ingredient in a single compartment. However, it is known in the field to provide capsules which hold two ingredients in two separate compartments. These are used when the ingredients should not be mixed together inside the capsule. For an example of same see FIG. 1, which is the sole figure in Netherlands patents No. 7,610,038 issued to Tapanahony N. V. on 13 Mar. 1978. This shows in a cross section such a two-compartment capsule 10 having a body 11, which defines a first chamber or compartment holding a first ingredient B. The inner wall of the body portion is indicated at 12. Extending into the body is what may be referred to as a diaphragm 16, which includes a lower curved portion and which holds in a second compartment defined by its upper surface a second ingredient A. The inner surface of the diaphragm is indicated at 17. The cap 15 is shown as having a typical curved upper end and an inner surface 14. The upper end of the diaphragm is indicated at 13. Typically ingredients A and B are different materials.
A different two-compartment capsule is shown similarly in cross-section in present FIG. 2 from French patent No. 1,454,013 issued to Pluripharm on 22nd of August 1966. This similarly has a body 23, which contains a first ingredient C and an upper compartment defined by the diaphragm 24 which contains the second ingredient D with the cap 25 extending over the outside of the body p 23. Here the diaphragm 24 sidewalls extend all the way up to contact the inner surface of the cap 25 to contain ingredient D.
However, such two-compartment capsules are not believed to be in wide (if any) commercial use likely due to the difficulties of successfully making and filling same in large volume. The present inventors, moreover, have determined there are several technical deficiencies with these known two-compartment capsules. They identified two such aspects, which it is believed are not properly addressed up to now. One is during assembly of the capsule (when it is being filled with the ingredients) to provide proper alignment of the diaphragm that results in an even edge at the top of the capsule/diaphragm mouth, allowing for a good seal surface at both at the tops and the sides of the diaphragm. This technical problem may be addressed by the sidewalls of the diaphragm 24 in FIG. 2 extending to the top of the cap. Further, the present inventors have determined that the sidewall contact between the diaphragm and the body in the prior art is not sufficient to provide proper overall integrity and robustness of a capsule during and after filling and assembly of the capsule.